The Eunice Kennedy Shriver National Institute of Child Health and Human Development (NICHD) and the National Institute of Neurological Disorders and Stroke (NINDS) were also natural partners in the project because of their interest in healthy brain development, the interactions between environmental factors and brain development, and the effects of childhood sports. There is much we do not know about the impact of contact sports and non-contact sports on brain function, particularly for this age group. On one hand, the physical activity and social interactions provided by youth sports can be strong positive influences on physical and mental health; however, an estimated 630,000 U.S. emergency department visits annually are accounted for by children who present with symptoms of traumatic brain injury (Faul et al., 2010), and up to 13% of them continue to experience physical and/or cognitive symptoms more than 3 months after the injury (Barlow et al., 2010). Increasing societal awareness of the risk for traumatic brain injury during organized sports has made this a specific and pressing question, not only for researchers but also for parents, educators, and
